Astronomers seize last chance in lifetime to see alignment of Earth, Venus and the Sun

By Agence France-PresseSaturday, May 26, 2012 16:25 EDT

Astronomers are gearing for one the rarest events in the Solar System: an alignment of Earth, Venus and the Sun that will not be seen for another 105 years.

The celestial ballet known as the Transit of Venus is one of the most eagerly-awaited events in skywatching, an episode that has advanced the frontiers of knowledge, sometimes with dramatic consequences.

“For centuries, the Transit of Venus has been one of the great moments for astronomers,” said Claude Catala, head of the Paris Observatory. “2012 will not be an exception to the rule. It is a one-off opportunity.”

“It’s now or never,” the British magazine Physics World told its readers.

“It will be an event well worth watching, as the next Transit of Venus will not occur until December 2117, when most of us will be long gone.”

In a transit, Venus passes between Earth and the Sun, appearing through the telescope as a tiny black spot that, for some six and a half hours, crawls in a line over the fiery face of the Sun.

On the evening of June 5, North America, Central America and the northern part of South America will get to see the start of the transit — clear skies permitting — until those regions go into sunset.

All of the transit will be visible in East Asia and the Western Pacific.

Europe, the Middle East and South Asia will get to see the end stages of the eclipse as they go into sunrise on June 6.

But West and Southwest Africa, and most of South America, will not get a view, although people there can catch the event on a webcast.

Only six Transits of Venus have ever been recorded — quite simply because before the phenomenon was predicted by the 17th-century German mathematician Johannes Kepler, no-one knew where to look or had the lenses to do so.

Transits occur in truly weird combinations, either in a June or a December. When one happens, another one happens in the same month eight years later.

Then there is a wait.

A very long wait.

A pair of December transits follows a June pair after 105 years, while a June pair comes 121 and a half years after a December pair.

For example, there was a transit in December 1882; the next one was in June 2004, which will be followed this year on June 5-6, depending on the dateline; astronomers will then have to be patient until December 2117, which will be followed by another transit in December 2125.

In the 18th century, scientists realised that by timing the event from different locations, the transits of 1761 and 1769 could be triangulated and give the distance between Earth and the Sun — “the noblest problem in astronomy,” for it would at last place mankind in the cosmos.

Britain and France, the two superpowers at the time, jockeyed for the glory, dispatching missions to far-flung places.

Among them were British surveyors Charles Mason and Jeremiah Dixon, who were attacked by French warships just after they left Plymouth and headed back to port.

Discouraged, they wanted to cancel the trip — but ventured back out to sea after a receiving a now-legendary letter from the Royal Society, the British scientific academy which was sponsoring them.

To give up would “bring an indelible Scandal upon their Character, and probably end in their utter Ruin,” the letter said stonily.

Drama was also in store for the 1769 transit, when Britain sent James Cook to Tahiti to view the event from there.

After his mission, Cook opened the instructions for the secret — and most important — part of his expedition: to search for and map for the Crown a mysterious “southern continent,” which turned out to be New Zealand and eastern Australia.

For astronomers today, the Transit of Venus offers a chance to gain insights into the planet’s notoriously thick, cloudy atmosphere, and use the refraction of sunlight to finetune techniques for hunting planets orbiting distant stars.

One of the most useful exercises will be to compare observations of the transit made by Earth-based telescopes, orbitaltelescopes and robot probes, including Europe’s Venus Express.

“This way we get different measurements with which to calibrate our methods for analysing exoplanets orbiting other stars,” said Thomas Widemann, of the Laboration of Space Studies and Astrophysics Instrumentation, or LESIA, in Paris.

It would be as if the Sun was magnifying the archetypal intentions of the Venus transit retrograde through the portal of 16 Gemini in each individual Soul's chart/life. So wherever that 16 Gemini is in anyone's chart is where that archetypal intent will be magnified by the Sun.

"What has been 'discovered' not only needs to be discussed and tested through an intellectual exchange which permits its formulation, it also demands 'exteriorization'. This implies dealing with those who are still unaware of the new knowledge or realization....".

I was listening to Deva's discussion of the NN Gemini on Kristin's show recently, and if I have recalled correctly, JWG's NN is at 15+ (=16) Gemini. The above certainly seems apropos to the work he did.

I was also reading something written about Venus/Gemini by Howard Sassportas. In esotericism, Venus rules Gemini. The idea is that Venus can harmonize the dualities of Gemini, bringing them to higher vibration. This makes me think of Einstein's statement that a problem can't be solved at the level at which it was encountered....

Astronomers around the world will be using advanced telescopes to watch Venus cross in front of the Sun on June 5 and 6 in the hopes of finding clues in the hunt for other planets where life may exist.

By studying the atmosphere of a well-known planet in this once-in-a-lifetime event, scientists say they will learn more about how to decipher the atmospheres of planets outside our solar system as they cross in front of their own stars.

“There are many, many of these events that are observed for distant stars. The thing is that stars are just points of light because we are so far away, so you can’t actually see what is going on,” Alan MacRobert, astronomer and editor of Sky and Telescope magazine, told AFP.

However the transit of Venus, an event that will not happen again for another 105 years, or until 2117, offers a chance to practice decoding the atmosphere of a planet based on the impression it leaves on its star’s light.

“The idea is some of that starlight skims through the atmosphere of the planet and the atmosphere leaves its imprint on that tiny, tiny little bit of a star’s light,” MacRobert said.

“If you can separate that from the rest of the star’s light — analyzing the light before, during and after the transit and looking for the difference — you can actually tell something about the planet’s atmosphere,” he added.

“And this is absolutely at the cutting edge of present day technology.”

The beginning of the transit will be visible in North America, Central America and the northern part of South America on the evening of June 5, as long as the skies stay clear. The end will not be seen in these regions due to sunset.

All of the transit will be visible in East Asia and the Western Pacific.

Europe, the Middle East and South Asia will get to see the end stages of the eclipse as they go into sunrise on June 6.

However, due to the risk of blindness or painful, permanent eye damage, people should not look directly at the Sun without a proper solar filter to try and observe the tiny black dot crossing its surface.

Global astronomers are keenly searching the universe for hints of a rocky planet like Earth in the Goldilocks zone — not too hot and not too cold — with the right atmosphere and the existence of water to support life.

Experts believe the galaxy is teeming with billions of rocky planets that might be able to support life. Most have not yet been discovered by Earthlings, and are located so far away that they would be impossible to reach with modern technology.

The latest catalog released by NASA’s Kepler space telescope team in March showed a total of 2,321 planet candidates transiting 1,790 stars.

Ten of the 46 planet candidates found in the habitable zone where liquid water could exist are close to the size of Earth, according to NASA. But in most cases, scientists lack details about these planets’ atmospheres.

Even though Venus, the second planet from the Sun, is far too hot to be habitable and has a dense, C02 thick atmosphere, watching it transit the Sun is a valuable exercise for science.

“The fact that Venus is not in a habitable zone does not really matter,” said Rick Feinberg of the American Astronomical Society.

“It gives us an opportunity to study in very great detail something we are observing very much further away and gives us more confidence in our ability to interpret the signals we are getting.”

Feinberg added that the best times for scientists to watch the transit are the first and last 20 minutes, when sunlight filters through the Venus’s atmosphere as it forms a fine shell around the planet.

The US National Solar Observatory in Tucson, Arizona, will use telescopes in Arizona, New Mexico, California, Hawaii, Australia and India to monitor the transit and collect data.

“This one will help us calibrate in several different instruments, and hunt for extrasolar planets with atmospheres,” said Frank Hill, director of the NSO’s Integrated Synoptic Program.

In the 18th and 19th centuries, astronomers used transits to measure the distance of the Earth to the Sun, he added.

A small black dot will grace the face of the sun as it rises (over Europe) on Wednesday, when Venus makes a rare and historic journey across the burning disc of our parent star.

Few people alive today will have another chance to witness the transit of Venus, as the laws of orbital mechanics do not bring the planets into position again until December 2117.

In previous centuries, nations dispatched astronomers to their farthest territories to record the transit in progress. In doing so, they embarked on the first global scientific collaboration in history and answered the pressing question of the size of the solar system.

This year’s observations from powerful telescopes will help scientists learn more about planets far beyond our solar system, and may even help spot those with atmospheres that are similar to Earth’s and capable of harbouring life.

To celebrate the event, national space agencies, universities and amateur astronomers will point telescopes at the sky and trace Venus’s seven hours in the sun from 11.04pm on Tuesday until 5.55am BST the next morning.

The transit occurs when Venus moves directly between the Earth and sun, an event that happens less than once a century. It takes place in pairs eight years apart (the first in this pair was in 2004). Only the final stages of the transit will be visible from Britain, and then only if skies are clear on Wednesday morning, when the sun rises at 4.46am in London and 4.30am in Edinburgh.

The start of the transit will be visible from North and Central America and the north-western countries of South America. Parts of Asia and Australia will see the entire show.

Despite the early start, the Royal Astronomical Society said enthusiasts across the UK had organised transit parties and viewings from Ayrshire to St Austell and County Antrim to Whitby. Members of Ayrshire Astronomical Society are heading for a remote location off an unmarked road with three telescopes to witness the spectacle.

The equipment needed to watch the transit safely has its own language, with Graham Longbottom, president of Ayrshire Astronomical Society, speaking of Colorado Hydrogen Alpha solar scopes and Baader-filtered white light scopes. Though Venus will be visible to the naked eye, observers should never look at the sun directly, and even with eclipse goggles only for a few minutes at a time. One way to watch the transit safely is to project an image of the sun on to a screen, using a telescope or binoculars.

Subject to Scottish weather, Longbottom expects to watch the transit for two hours, though he is unsure how many will join him. “There is a lot of interest in astronomy at the moment as a result of TV coverage, but 4am on a Wednesday morning is likely to test the resolve of all but the really committed, and that includes society members,” he said.

The first observations of a transit of Venus came from Jeremiah Horrocks in Much Hoole, a tiny village in Lancashire. On 24 November 1639, Horrocks watched as the planet traversed the sun after projecting its image on to a sheet of paper through a small telescope. He died two years later aged only 22.

The scientific importance of the transit was made clear by Edmund Halley, Britain’s second astronomer royal, who in 1716 called on nations to join forces and record the event from positions around the world. Timing the transit from different spots on Earth allowed astronomers to calculate the distance from our planet to the sun, and so work out the size of the solar system.

Halley’s essay was visionary, written nearly 50 years before the next transit was due in 1761. At the time, astronomers knew only relative distances in the solar system, for example, that Jupiter was five times further from the sun than Earth. Their best estimate of how far Earth lay from its star was 55m miles. “They didn’t know the distance from Earth to the sun, and that was a base unit. It was like having a map without the scale,” said Andrea Wulf, author of the 2012 book Chasing Venus: the Race to Measure the Heavens.

“What was so different was that no observation on its own would work, they had to be paired up. You had to send astronomers to as many, and as far apart, places as possible,” said Wulf. “This was the first truly global international collaboration which lays the foundations of modern science.”

The path Venus takes across the face of the sun varies depending on where the transit is viewed from. Halley’s method called for pairs of astronomers a known distance apart to time the start and end of the transit. Taken together, the astronomers used these figures to calculate the separation of the Earth and sun using trigonometry.

The British sent James Cook on the Endeavour to witness the transit from Tahiti, where his crew became so enamoured with the locals they made only cursory notes on the event. Others fared worse. The French astronomer Guillaume le Gentil was barred entry to Pondicherry for the first transit and watched hopelessly from sea. He stayed in the area to watch the second transit in 1769, only for cloud to obscure his view. On returning home, he discovered he had lost his job, and his heirs had divided up his estate, giving him up for dead.

Halley’s plan was a success despite the hardships of those who set out to observe the transit. The astronomers shared their records and eventually arrived at a new measurement for the distance between Earth and the sun of 93m to 97m miles. Today, the accepted distance is 92.96m miles.

“The transit has this remarkable history, going back to Horrocks and the amazing efforts that were made to observe it in the 18th and 19th centuries. It was the first enterprise in big science,” said Lord Rees of Ludlow, the astronomer royal. “Very careful measurements of what happens when the transit starts and ends may reveal that you can in principle learn something about the planet’s atmosphere and such like, and about the atmosphere of the star itself,” he added.

Rees said it was unlikely he would watch the transit this year though. “Down here in the south we have even less chance of seeing it than in Scotland. And it’s very early in the morning,” he said.

Key facts

When does it happen?

The last transit of Venus of the 21st century occurs on 5 and 6 June 2012 depending on where you are viewing from. The transit starts at 11.04pm BST, when it will be visible from the US. The final hour of the transit will be visible from the UK just before 5am BST on 6 June, clear skies permitting. The transit will not happen again until December 2117.

How long does the transit last?

Venus takes nearly seven hours to cross the face of the sun, but the event is divided into four “contacts” that mark different phases of the transit. Venus makes first contact when it encroaches onto the disc of the sun. Twenty minutes later, on second contact, the planet will be fully silhouetted. On third contact, at 5.37am BST, Venus will beginto leave the sun, and the transit will be over on fourth contact at 5.55am BST.

Where can I see it?

The whole transit is visible from Alaska, and parts of northern Canada, and from New Zealand, much of Australia, Asia and Russia. In the US, the transit will be in progress as the sun sets on 5 June. In East Africa, Europe and Scandivia, the transit will be under way as the sun rises on 6 June. Much of South America and western Africa will not see the event.

How can I watch it safely?

Never look directly at the sun, it will damage your eyes. You can use eclipse viewing glasses that carry a CE mark and are not damaged or worn, but only for a few minutes at a time. Venus is large enough to see with the naked eye and will appear as a spot about 1/32 the width of the sun. It is not safe to look at the sun through regular sunglasses. For a better view, use a small telescope or a pair of binoculars to project an image of the sun on to a screen.

Can I watch online?

Nasa will broadcast a live webcast of the transit from the Mauna Kea Observatories in Hawaii.

Australia was gearing up Tuesday for the transit of Venus, an event with historical significance as a previous occurrence in 1769 played a key part in the “discovery” of the southern continent.

When Venus on Wednesday passes between the Earth and the Sun, an astronomical event that will not occur again until 2117, millions of people will be gazing to the skies, just as Englishman Captain James Cook did in the 18th century.

Cook was not just a keen sailor but also an avid watcher of the planets and in 1768 he set sail for Tahiti on HMS Endeavour to record the phenomena that occurred in 1769.

It was one of only six transits ever observed since the invention of the telescope — in 1639, 1761, 1769, 1874, 1882 and 2004.

After a successful observation he was sent to seek the “great south land” thought to exist in the Pacific Ocean during which he discovered and charted the east coast of Australia, staking a British claim in 1770.

Australia was first settled as a British colony in 1788.

“Culturally, for modern Australia it’s a very significant event,” Sydney Observatory senior education officer Geoffrey Wyatt said of the transit.

“It is technically just a little black spot on the sun, but historically it’s so important for us.”

Weather permitting, Australia will be one of the best places to observe the spectacle as the entire transit is set to be visible from eastern and central parts of the country.

A series of events are due to be held, with viewings through telescopes adapted to protect the eye, but forecasters have put a dampener on expectations of seeing Venus cross in front of the sun.

A major storm front was closing in on Sydney Tuesday, bringing gale force winds and torrential rain, which are set to extend into Wednesday.

The transit is due to begin Tuesday evening in North and Central America.

Linda thanks for posting those awesome pictures. Below are a couple more from NASA. I watched this Venus transit live through one of the NASA telescopes available on the internet. It was simply awesome.

God Bless, Rad

Originally published Tuesday, June 5, 2012 at 6:13 AM

Silhouetted Venus reminder of solar system's size

Filtering the sun's light to a miniscule fraction of its true power allowed sky-gazers over the world to watch a silhouetted Venus travel across Earth's closest star, an extremely rare spectacle that served as a reminder of how tiny our planet really is.

By OSKAR GARCIA

Associated Press

HONOLULU —

Filtering the sun's light to a miniscule fraction of its true power allowed sky-gazers over the world to watch a silhouetted Venus travel across Earth's closest star, an extremely rare spectacle that served as a reminder of how tiny our planet really is.

After all, the next transit is 105 years away - likely beyond all of our lifetimes but just another dinky speck in the timeline of the universe.

"I'm sad to see Venus go," electrical engineer Andrew Cooper of the W.M. Keck Observatory told viewers watching a webcast of the transit's final moments as seen from the nearly 14,000-foot summit of Mauna Kea volcano on Hawaii's Big Island.

From Maui to Mumbai, Mexico to Norway, much of the world watched the 6-hour, 40-minute celestial showcase through special telescopes, live streams on the Internet or with the naked eye through cheap cardboard glasses.

"If you can see the mole on Cindy Crawford's face, you can see Venus," Van Webster, a member of the Los Angeles Astronomical Society, told anyone who stopped by his telescope for a peek on Mount Hollywood.

For astronomers, the transit wasn't just a rare planetary spectacle. It was also one of those events they hoped would spark curiosity about the universe and our place in it.

Sul Ah Chim, a researcher at the Korea Astronomy and Space Science Institute in South Korea, said he hoped people see life from a larger perspective, and "not get caught up in their small, everyday problems."

"When you think about it from the context of the universe, 105 years is a very short period of time and the Earth is only a small, pale blue spot," he said.

The transit began just after 6 p.m. EDT in the United States. What observers could see and for how long depended on their region's exposure to the sun during that exact window of time, and the weather.

Those in most areas of North and Central America saw the start of the transit until sunset, while those in western Asia, the eastern half of Africa and most of Europe could catch the transit's end once the sun came up.

Hawaii, Alaska, eastern Australia and eastern Asia including Japan, North and South Korea and eastern China get the whole show since the entire transit happens during daylight in those regions.

While astronomers used the latest technology to document the transit, American astronaut Don Pettit aboard the International Space Station was planning to take photos of the event and post them online.

Online streams with footage from telescopes around the world proved popular for NASA and other observatories. A NASA stream midway through the transit had nearly 2 million total views and was getting roughly 90,000 viewers at any given moment.

Meanwhile, terrestrial stargazers were warned to only look at the celestial event with a properly filtered telescope or cardboard eclipse glasses. If the sun is viewed directly, permanent eye damage could result.

Roy Gal, an assistant astronomer at the University of Hawaii, told those viewing the transit at Waikiki Beach on Oahu that the telescopes were filtered to block all but 1/100th of 1 percent of the sun's light, plus all its infrared rays to keep the instruments from overheating.

"What we need to do is block out most of the light from the sun so that we don't go blind and we don't melt things," Gal said in an interview.

In Los Angeles, throngs jammed Mount Hollywood where the Griffith Observatory rolled out the red carpet for Venus. The last time the city witnessed a Venus transit was 130 years ago in 1882. A 2004 transit was not visible from the western U.S.

Telescopes with special filters were set up next to the lawn and people took turns peering at the sun before and during the transit. Astronomers and volunteers lectured about the rarity of a Venus pass to anyone who would listen.

Minutes before Venus first touched the outer edge of the sun, Sousa's "Transit Of Venus March" blared through. The crowd turned their attention skyward.

Jamie Jetton took the day off from work to bring her two nephews, 6 and 11, visiting from Arizona to the observatory. Sporting eclipse glasses, it took a little while before they spotted Venus.

"I'm still having fun. It's an experience. It's something we'll talk about for the rest of our lives," she said.

Bo Tan, a 32-year-old software engineer took a half day off from work and went with his co-workers to the observatory. He admitted he wasn't an astronomy buff but could not miss this opportunity.

He pointed his eclipse glasses at the sun and steadied his Nikon camera behind it to snap pictures.

"It makes you feel like a small speck in the universe," he said.

Clouds obscured the view in Tokyo, but students and other viewers under clearer skies in southern and western Japan were seen on TV using dark lenses to gaze at the sun. One child remarked that it looked as if the "sun had a mole on its face."

In India, where astrology is so popular it influences decisions from when to get married to who should run for office - hundreds of enthusiasts from children to the elderly massed at New Delhi's planetarium to see Venus cut a path across the Sun.

"Celestial events, especially rare ones like this, generate a lot of public interest," said Rathnasree Nandivada, director of the planetarium. During the last Venus transit in 2004, more than 10,000 people visited the planetarium.

There was no disappointment, however, for those who watched the planetarium's webcast of the celestial event from India's Astronomical Observatory in the Himalayan region of Ladakh - the world's highest observatory, at 14,800 feet (4,511 meters).

The low oxygen and air pressure along with minimal cloud cover over the station provide optimal conditions for sky viewing, according to Raghu Kalra, one of several volunteers for the Amateur Astronomers Association who provided the webcast feed from Ladakh.

In Mexico, at least 100 people lined up two hours early to view the event through telescopes or one of the 150 special viewing glasses on hand, officials said. Observation points were also set up at a dozen locations.

Venus, which is extremely hot, is one of Earth's two neighbors and is so close in size to our planet that scientists at times call them near-twins. During the transit, it will appear as a small dot.

This will be the seventh transit visible since German astronomer Johannes Kepler first predicted the phenomenon in the 17th century. Because of the shape and speed of Venus' orbit around the sun and its relationship to Earth's annual trip, transits occur in pairs separated by more than a century.

It's nowhere near as dramatic and awe-inspiring as a total solar eclipse, which sweeps a shadow across the Earth, but there will be six more of those this decade.

In Hawaii, hundreds of tourists and locals passed through an area of Waikiki Beach where the University of Hawaii set up eight telescopes and two large screens showing webcasts of the transit as seen from telescopes at volcanoes on other Hawaiian islands.

But minutes after Venus crossed into the sun's path, clouds rolled overhead and blocked the direct view.

"It's always the challenge of being in Hawaii - are you going to be able to see through the clouds," said Greg Mansker, 49, of Pearl City, as he stood in line at a telescope.

The intermittent clouds didn't stop people from looking up through filters, but it did drive some to crowd the screens instead.

Jenny Kim, 39, of Honolulu, said she told her 11-year-old son the planet's crossing would be the only time he'd get to see the transit in person.

"I don't know what the future will be, so I think this will be good for him," Kim said as she snapped photos of the webcast with her smartphone.

Astronomers also hosted viewings at Pearl Harbor and Ko Olina. In Maui, 20 couples renewed their vows during a ceremony tied to the transit at the Hyatt Regency Maui, a spokeswoman said.

Some observers at the University of Alaska, Anchorage gathered on a campus rooftop, peering at Venus through special filtered glasses and telescopes.

"It's not really spectacular when you're looking at it," Kellen Tyrrell, 13, said. "It's just the fact that I'm here seeing it. It's just so cool that I get to experience it."

NASA planned a watch party at its Goddard Visitor Center in Maryland with solar telescopes, "Hubble-quality" images from its Solar Dynamics Observatory Mission and expert commentary and presentations.

Most people don't tend to gaze at the sun for long periods of time because it's painful and people instinctively look away. But there's the temptation to stare at it during sky shows like solar eclipses or transits of Venus.

The eye has a lens and if you stare at the sun, it concentrates sunlight on the retina and can burn a hole through it. It's similar to when you hold a magnifying glass under the blazing sun and light a piece of paper on fire.

It can take several hours for people to notice problems with their eyes but, by that time, the damage is done and, in some cases, irreversible.

During the 1970 solar eclipse visible from the eastern U.S., 145 burns of the retina were reported, according to the American Academy of Ophthalmology.

Experts from Hong Kong's Space Museum and local astronomical groups were organizing a viewing Wednesday outside the museum's building on the Kowloon waterfront overlooking the southern Chinese city's famed Victoria Harbor.

On the East Coast of the United States, amateur astronomer Vince Sempronio was at a viewing hosted by Montgomery College in Takoma Park, Md., but clouds there - as in many other places - limited visibility of the spectacle. Many at the college viewing crowded around a laptop to watch the NASA webcast instead of the Venus move across the sun.

"I was here at the same spot eight years ago when we had the last transit and I was able to show people, using my telescope then. So I'm not too disappointed," Sempronio said. "If modern science and medicine helps, maybe I'll be around in a hundred and five years to see the next one. But I'm not crossing my fingers."

Below are two links. The first one goes to a series of pictures taken of the Venus transit by photographers from around the world. They are beautiful. The second link goes to a NASA movie taken of the Venus transit across the face of the Sun that is just stunning. Just to enjoy.